The present invention relates to crab butchering apparatus or crab cleaning apparatus.
There are problems that are specifically encountered with the types of crabs known as Snow (or Tanner) and King Crab. The legs of these crabs are long and slender, tapered toward the tip, with the exception of the pincers. The pincers on the Snow crab are virtually the same size as each other and are larger in diameter than the other legs. The King crabs are substantially larger than Snow crabs and there is quite a little disparity between the left and right pincer size and the leg size. Hence the machine for King crab must be substantially larger than that for Snow crab but (omitting the pincer separator which will not work on King crab because of the pincer size disparity) otherwise identical. Unlike the King, Snow "tails" have no meat and must be removed and disposed of. One problem confronting the processor of crabs in general is that the crabs must still be alive when processing begins. Live crab butchering is required because toxins build up in crab bodies after death and with the practice of "live tanking" (that is, holding crabs alive in a tank by pumping fresh seawater through the tank) there is no way of determining how long a crab has been dead or what conditions might have occurred which would affect the level of toxins.
Consequently, in the industry, butchers handle live and moving crabs. The butcher must: grasp the crab, separate it from the others while it often has a hold on another crab, corral all of the legs so that he can butcher and clean the crab adequately, (that is, knock the carapace off, brush the gills off, shake the guts out, and split the body into sections), and place the sections on a transfer belt or the like. While a practiced butcher can accomplish these steps rather quickly, one butcher must still accomplish all steps. Subsequently the legs are normally sawed from the bodies and separated from the pincers.
When a crab butchering and cleaning machine is considered, all these steps must still be performed so that substantially the same ends are accomplished. Some type of firm hold is required and an additional problem arises when removing the back or carapace. The pincers tend to fold in towards the mouth when the carapace is removed and if a saw is used by the machine in a subsequent operation, damage to the pincers can result if they are not kept in a spread-out position.
Processing can be accomplished in two types of processing lines: the first type of processing line involves a section line, wherein the carapace is removed, the guts and gills cleaned and removed from the crab, thereafter the crab body is halved so as to leave the final product of two body halves, each with attached legs and pincers. The second type is a meat line, wherein the above processing is substantially the same and in addition the legs are removed from the body, so that the individual legs may thereafter be rolled to extrude the meat from the legs from the hole where the legs were removed from the body without tearing or "splitting" the meat. Generally speaking, the larger the size of a single piece of meat, the more valuable it is per pound. Thus, the merus segment (i.e., the large leg segment next to the body) is potentially the most valuable segment on these types of crab. Therefore, the legs are separated from the body with an eye for the optimum recovery of the merus, so that the cut should be made as close to the body as possible to obtain the greatest length of the merus, but sufficiently far from the body to provide an adequately sized hole for the above-mentioned extruding. After the legs are separated from the body, they are partially cooked and then fed into a roller for the removal of the meat. Bodies are also cooked and rolled to remove meat. This is normally not done on the same equipment as the legs. Pincers are usually handled and sold separately.
From the above, it can be seen that a butchering machine should be capable of: (1) a feeding method to easily deal with a live crab; (2) detaching carapaces and removing them; (3) detaching tails and removing them; (4) removing the guts and gills from the body; (5) producing legs and bodies cut for optimum merus meat recovery; (6) producing claws with minimum damage so the processors have all marketing options intact; (7) isolating the three components (bodies, legs and claws) to facilitate separate handling and processing; (8) producing sections only in the event that sections are called for; and accomplishing all of the above in a fast, efficient manner with maximum automation and minimum cost, both initially and with respect to running the machine.
To feed a machine such as that of the present invention, a live crab would be tossed into a conventional "kill box" facing in the direction of travel, where it would be rapidly killed by steam or some other method after several seconds of exposure and thereafter delivered quickly into the entrance of the butchering machine, so that the crab is alive when processing is initiated but handling problems caused by the crabs movements are substantially reduced.